Zeuxis, (flourished 5th century bc, Heraclea, Magna Graecia [Italy]), one of the best-known painters of ancient Greece, who seems to have carried a trend toward illusionism to an unprecedented level.

Zeuxis was, in one ancient account, a pupil of Demophilus of Himera in Sicily; other sources refer to him as a pupil of Neseus of Thasos (an island in the northern Aegean Sea). He seems to have been a panel painter rather than a wall painter; he preferred small compositions, often a single figure, and broke with a lofty tradition by introducing genre subjects into monumental painting.

Although none of his works survives, the subject matter of several have been recorded by ancient writers: they include pictures of the gods, such as Zeus surrounded by other deities, Eros crowned with roses, and Pan; pictures of other mythological figures, such as Marsyas bound, a centaur family, and the infant Heracles strangling two serpents in the presence of his parents Alcmene and Amphitryon; portraits of the Homeric figures Helen, Menelaus, and Penelope; and genre pictures: an athlete, an old woman, a boy with grapes, and a still life of grapes. There are also references to his monochrome paintings and to works in clay.

Ancient records also describe his technique. Following the initiative of his Athenian contemporary Apollodorus, Zeuxis used shading to produce a rudimentary form of chiaroscuro, as opposed to the older method of merely filling in the outlined figures with flat washes of colour. The interior modeling of Zeuxis’ figures would appear strongly realistic as compared with the flat volumes of the older method, and this revolutionary illusionism was probably the basis of such stories as that of the pictorial contest in which Zeuxis painted a bunch of grapes so realistic that birds flew toward it to take a nibble. In 18th- and 19th-century art theory these stories were often used to recommend the procedures of the ancients to modern artists who aimed at effective imitation.